Valve-operating mechanism for internal-combustion engines



W. W. DOUGLAS AND S. L. BAILEY. v VALVE OPERATING MEGHANISM FOR INTERNALCOMBUSTION ENGINES.

. APPLICATION FILED MAY I2. IsIs. 1,399,941 Patented Dec. 13, 1921.

III-IE MQ v f I ff f z UNITED STATES PATENT oFF-ICE.

WILLIAM WILSON DOUGLAS AND STEPHEN LESLIE BAILEY, 0F BRISTOL, ENGLAND. I

VALVE-OPERATING- MECHANISM FOR INTERNAL-COMBUSTION ENGINES.

'application med may 12',

To ZZ whom t 'may concern.'

Be it known that we, WILLIAM WILSON DOUGLAS and STEPHEN LESLIE BAILEY, subjects of the King of England, residin at Bristol, in the county of Gloucester, ng-

-land, have invented certain new and uselemployed between each valve tappet and its operating cam.

The object of the invention'is. to provide a simple and, symmetrical system ermitting of both cylinders being alike wlth -uniform timing of both valves.

In the accompanyingv drawings,

Figure 1 is a horizontal sectlonshowing part of an engine to which this invention has been applied, and

Fig. 2 is a side elevation of the same with one cylinder removed.

v Like lletters indicate like 4parts throughoutthe drawings.

These show a horizontal opposed twincylinder engine of known type, wherein the exhaust valve stem A 4and tappet A2 of the one cylinder Y is parallel to, but not coaxial with, the corresponding exhaust lvalve stem B and tappet B2 of the 'other cylinder Z. In this case a vertical camshaft C is employed, the axis of which is situated so that the center lines of the tappets A2 and B2 are offset in the horizontal plane at equal distances on either side of it, as will be clearly seen. The rockers D which are of known construction, swing in a horizontal plane about 'vertical pivots D2, which are situated alike with reference to the adjacent valve-tappets and the axis of the cam shaft. It is important that the rockersl be similarly disposed relatively to plate may be interchangeable.

Specification of Letters Patent. Patented ,Dem 13, 1921.

1919. seria! No. 296,366.-

the direction 'of the rotation of the cam, so that the valve lift diagrams of both valves may be' the same.

The cam-shaft C and rockers are carried (the former in bearings at J) upon a frame or plate E which is-detachably mounted upon the engine crankcase F so .that it constitutes in itself af unit.

To provide for relievin the compression in known manner by ralsing the exhaust valves off Vtheir seatings, .a supplementary cam R may be provided having swells on opposite sides.- This cam is formed on a sleeve R2 loosely mounted on the cam shaft C, and operativel connected to a hand-con trolled plunger lby which it is normally held stationary, by the spring T with its cam swells inoperative. On moving the plunger S to the left in Fig. 2. the two cam swells are brought into contact with the two x''" haust-valve rockers D, whichfare -made Asuficiently wide for this purpose, and thus the two exhaust-valves are simultaneously' lifted.

The inlet-valves (one of which is shown i.

at O) are operated by a cam N and rockers' M arranged similarly to those employed for the exhaust-valves. The cam-shaft C' may be extended and provided with gearing at L to operate the shaft K which may operate a magneto or any other device.

In an engine of the opposed cylinder type the cylinder axes are generally out of v line with one another. Preferably the amount of this offset in this case is the 'same vas that of the Atwo valve stemsin relation to one another, so that the distance of each valve stem from its cylinder axis is the same in both cases, and the cylinders com- What we'claim asour'invention and desire to secure by Letters Patent is l. In an internal combustion engine of the haust valves, the tappets of each pair being f oiset relative to each other inthe samerelationship as the two cylinders, a single cam provided on said cam shaft for each pair of tappets, and a pairof rockers provided for each pair of tappets and arranged sym-` metrically on opposite sides of the aXis of saidcam extending in opposite directions.

2. The combination as set forth in claim 1 including the engine crank casing and a platedetachably mounted on Said 4casing and carrying the cam-shaft and the oppo- .of two subscribing witnesses.

WILLIAM WILsoNDoUGLAs. STEPHEN LESLIE BAILEY.

Witnesses:

ALFRED H. HARRISON, F. C. DUNN. 

